Abstract In this study, the aim was to evaluate whether there is variability in the protein nutritional composition of grains between maize genetic bases (simple hybrids, triple hybrids, double hybrids and varieties) and sowing dates, and predict digestible amino acids for pigs based on crude protein and meteorological variables. 773 grain samples from four maize genetic bases cultivated on ten sowing dates were evaluated using Near Infrared Reflectance Spectroscopy. Simple linear regressions were performed for protein nutritional traits in different genetic backgrounds and sowing dates. Principal component analysis was used to group data on the protein nutritional composition of grains and meteorological variables, by genetic bases and sowing dates. There is variation in the digestible levels of the eleven amino acids in grains between maize genetic bases and sowing dates. Maize varieties have the highest digestible levels of eleven amino acids in the grains, compared to simple hybrids, triple hybrids and double hybrids, regardless of the sowing date. Sowings carried out in October and November show higher digestible levels of the eleven amino acids in maize grains, in relation to sowings in the months of September, December, January and February, regardless of the genetic basis. The digestible contents of methionine, cystine, threonine, valine, isoleucine, leucine, phenylalanine, histidine and arginine in maize kernels can be predicted from crude protein with high accuracy, on all genetic bases.
Loro et al. (Wed,) studied this question.